Add option to customize configuration on @ConfigureWireMock annotation (#18)

Fixes #16

Author: maciejwalkowiak

README.md

@@ -70,6 +70,33 @@ It can be changed with setting `stubLocation` on `@ConfigureWireMock`:
 @ConfigureWireMock(name = "...", property = "...", stubLocation = "my-stubs")
 ```
 
+### Advanced configuration
+
+More advanced configuration can be applied through configuration customizers:
+
+```java
+@ConfigureWireMock(
+        name = "todo-service",
+        property = "todo-service.url",
+        configurationCustomizers = SampleConfigurationCustomizer.class
+)
+```
+
+Where `SampleConfigurationCustomizer` is a class implementing `WireMockConfigurationCustomizer`:
+
+```java
+class SampleConfigurationCustomizer implements WireMockConfigurationCustomizer {
+
+    @Override
+    public void customize(WireMockConfiguration configuration, ConfigureWireMock options) {
+        // apply changes to configuration
+    }
+}
+```
+
+> [!IMPORTANT]  
+> `WireMockConfigurationCustomizer` must have a no-arg constructor.
+
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 ## 🙏 Credits

wiremock-spring-boot/src/main/java/com/maciejwalkowiak/wiremock/spring/ConfigureWireMock.java

@@ -4,6 +4,7 @@
 import java.lang.annotation.RetentionPolicy;
 
 import com.github.tomakehurst.wiremock.WireMockServer;
+import com.github.tomakehurst.wiremock.core.WireMockConfiguration;
 import com.github.tomakehurst.wiremock.extension.Extension;
 
 /**
@@ -50,4 +51,11 @@
      * @return the extensions
      */
     Class<? extends Extension>[] extensions() default {};
+
+    /**
+     * Customizes {@link WireMockConfiguration} used by {@link WireMockServer} instance. Customizers are ordered by their natural order in this array. Each customizer must have no-arg constructor.
+     *
+     * @return the configuration customizers classes
+     */
+    Class<? extends WireMockConfigurationCustomizer>[] configurationCustomizers() default {};
 }

wiremock-spring-boot/src/main/java/com/maciejwalkowiak/wiremock/spring/WireMockConfigurationCustomizer.java

@@ -0,0 +1,12 @@
+package com.maciejwalkowiak.wiremock.spring;
+
+import com.github.tomakehurst.wiremock.core.WireMockConfiguration;
+
+/**
+ * Customizes {@link WireMockConfiguration} programmatically. Can be registered with {@link ConfigureWireMock#configurationCustomizers()}.
+ * Customizer must have public no-arg constructor.
+ */
+public interface WireMockConfigurationCustomizer {
+
+    void customize(WireMockConfiguration configuration, ConfigureWireMock options);
+}

wiremock-spring-boot/src/main/java/com/maciejwalkowiak/wiremock/spring/WireMockContextCustomizer.java

@@ -6,6 +6,7 @@
 
 import com.github.tomakehurst.wiremock.WireMockServer;
 import com.github.tomakehurst.wiremock.core.WireMockConfiguration;
+import org.junit.platform.commons.util.ReflectionUtils;
 import org.junit.platform.commons.util.StringUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -56,8 +57,6 @@ public void customizeContext(ConfigurableApplicationContext context, MergedConte
     }
 
     private void resolveOrCreateWireMockServer(ConfigurableApplicationContext context, ConfigureWireMock options) {
-        LOGGER.info("Configuring WireMockServer with name '{}' on port: {}", options.name(), options.port());
-
         WireMockServer wireMockServer = Store.INSTANCE.findWireMockInstance(context, options.name());
 
         if (wireMockServer == null) {
@@ -70,6 +69,10 @@ private void resolveOrCreateWireMockServer(ConfigurableApplicationContext contex
                 serverOptions.extensions(options.extensions());
             }
 
+            applyCustomizers(options, serverOptions);
+
+            LOGGER.info("Configuring WireMockServer with name '{}' on port: {}", options.name(), serverOptions.portNumber());
+
             WireMockServer newServer = new WireMockServer(serverOptions);
             newServer.start();
 
@@ -95,6 +98,19 @@ private void resolveOrCreateWireMockServer(ConfigurableApplicationContext contex
         }
     }
 
+    private static void applyCustomizers(ConfigureWireMock options, WireMockConfiguration serverOptions) {
+        for (Class<? extends WireMockConfigurationCustomizer> customizer : options.configurationCustomizers()) {
+            try {
+                ReflectionUtils.newInstance(customizer).customize(serverOptions, options);
+            } catch (Exception e) {
+                if (e instanceof NoSuchMethodException) {
+                    LOGGER.error("Customizer {} must have a no-arg constructor", customizer, e);
+                }
+                throw e;
+            }
+        }
+    }
+
     private String resolveStubLocation(ConfigureWireMock options) {
         return StringUtils.isBlank(options.stubLocation()) ? "wiremock/" + options.name() : options.stubLocation();
     }

wiremock-spring-boot/src/test/java/com/maciejwalkowiak/wiremock/spring/WireMockConfigurationCustomizerTest.java

@@ -0,0 +1,59 @@
+package com.maciejwalkowiak.wiremock.spring;
+
+import com.github.tomakehurst.wiremock.WireMockServer;
+import com.github.tomakehurst.wiremock.core.WireMockConfiguration;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.util.TestSocketUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@SpringBootTest(classes = WireMockConfigurationCustomizerTest.AppConfiguration.class)
+@EnableWireMock({
+        @ConfigureWireMock(
+                name = "user-service",
+                property = "user-service.url",
+                configurationCustomizers = WireMockConfigurationCustomizerTest.SampleConfigurationCustomizer.class
+        ),
+        @ConfigureWireMock(
+                name = "todo-service",
+                property = "todo-service.url",
+                configurationCustomizers = WireMockConfigurationCustomizerTest.SampleConfigurationCustomizer.class
+        ),
+})
+class WireMockConfigurationCustomizerTest {
+    private static final int USER_SERVICE_PORT = TestSocketUtils.findAvailableTcpPort();
+    private static final int TODO_SERVICE_PORT = TestSocketUtils.findAvailableTcpPort();
+
+    static class SampleConfigurationCustomizer implements WireMockConfigurationCustomizer {
+
+        @Override
+        public void customize(WireMockConfiguration configuration, ConfigureWireMock options) {
+            if (options.name().equals("user-service")) {
+                configuration.port(USER_SERVICE_PORT);
+            } else {
+                configuration.port(TODO_SERVICE_PORT);
+            }
+        }
+    }
+
+    @SpringBootApplication
+    static class AppConfiguration {
+
+    }
+
+    @InjectWireMock("user-service")
+    private WireMockServer userService;
+
+    @InjectWireMock("todo-service")
+    private WireMockServer todoService;
+
+    @Test
+    void appliesConfigurationCustomizer() {
+        assertThat(userService.port()).isEqualTo(USER_SERVICE_PORT);
+        assertThat(todoService.port()).isEqualTo(TODO_SERVICE_PORT);
+    }
+
+}